Extension card · Plithogenic
Plithogenic MOORA
This is the form of MOORA for situations where criterion scores are given as a truth-indeterminacy-falsity triple and criteria carry a degree of contradiction relative to one another. It runs the ratio system on this triple and arrives at a single net score.
Base method
MOORA →
Philosophy, mechanics, strengths and weaknesses are on the base method card; this card describes only the difference.
Data type (family)
Plithogenic →
What this data type is, when to use it, how to write it in a cell: the family's full account is here.
What Changes from the Base Method?
Cells. In crisp MOORA every cell is a single number. Here every cell is three numbers: truth (T), indeterminacy (I), falsity (F). One criterion is taken as dominant, with a contradiction degree of zero; how strongly the other criteria oppose this dominant criterion is given by a fixed, per-criterion contradiction degree between 0 and 1. This degree is the same for every alternative under a given criterion and does not vary from one alternative to another. Criterion weights are an input separate from the contradiction degree and arrive from outside as crisp numbers.
Scale equalisation. Crisp MOORA divides each column by the square root of the sum of its squared values. Here every cell is first adjusted by its own criterion's contradiction degree: truth is pulled upward towards the dominant criterion, while indeterminacy and falsity are shrunk by the same proportion. A single score is then drawn from this adjusted triple (truth positively weighted, indeterminacy weighted twice and negatively, falsity negatively weighted). Since the score can fall between −1 and 1, it is shifted by adding 1, and is then normalised, as in crisp MOORA, by dividing by the square root of its own column magnitude. The triple is not reversed for a cost criterion; as in crisp MOORA, the direction difference is carried by sign in the addition-and-subtraction step that follows.
Ratio system. The normalised, shifted scores are weighted; the sum over "more is better" criteria has the sum over "less is better" criteria subtracted from it. This is exactly the same operation as crisp MOORA's ratio system; the only difference is that the input has already been reduced to a T-I-F score through contradiction adjustment.
Result and defuzzification. Contradiction adjustment and score extraction are themselves the defuzzification, and they take place at MOORA's first step, not at its end. DecisionMind also lists the reference-point approach in this family as a step, but that step simply copies the ratio system's score as it stands; it produces no separate calculation of its own. In effect, therefore, the only approach that actually operates in this extension is the ratio system.
DecisionMind fixes the contradiction adjustment, the score function and the vector normalisation in classical Plithogenic MOORA. Weights and contradiction degrees are taken from outside and separately from one another; the method generates neither.
How to Read the Output
The output is a net score and a rank, as in crisp MOORA, and is read the same way: it is neither a percentage nor a probability, and it is not compared with a different analysis. The difference is here: beneath the score lie both T-I-F indeterminacy and an assumption about the degree of contradiction between criteria. In the illustrative example below, this assumption reverses the ranking of A1 and A3 with a small change; A2 stays ahead in every scenario.
Thus instead of writing:
"Plithogenic MOORA gives a more reliable result because it also accounts for contradiction"
the report should read:
"The contradiction degree between criteria has been given under the following assumption; A2 has the highest net score, while the ranking of A1 and A3 is sensitive to this assumption"
Taking contradiction into account does not automatically make the result more correct; it merely makes visible which assumption is influencing the ranking.
When to Prefer This over the Base Method
Use this extension when your criterion scores are given as a truth-indeterminacy-falsity triple, and some criteria carry information that is more "independent", or more "in conflict", than others. If the T-I-F triple alone is sufficient and no such dominance-contradiction relationship exists among the criteria, neutrosophic MOORA (n-moora) is already sufficient; the plithogenic form adds one further assumption, and if that assumption is given without justification it creates a spurious distinction.
Converting a measured criterion into a T-I-F triple is manufacturing indeterminacy, not modelling it. If the table is mixed, DecisionMind requires a single data type. The exit condition is the same as for crisp MOORA: if no compromise is acceptable on one criterion, this extension too is compensatory and will not eliminate anything below a threshold.
Mistakes Specific to This Extension
Violating the value space. Every cell must be a valid T, I, F triple, and a contradiction degree must be declared for every criterion; running the method with a missing or invented contradiction degree invalidates it.
Assigning the contradiction degree without justification. In the illustrative example, raising C2's contradiction degree from 0.33 to 0.55 reverses the ranking of A1 and A3. If this degree is given "by feel", the ranking becomes a feeling too; the degree must rest on a measurable justification for how independent, or how overlapping, a criterion's information is relative to the dominant criterion.
Choosing the dominant criterion arbitrarily. Which criterion is taken to have zero contradiction is a decision and must be justified in the report; if the dominant criterion changes, the contradiction degrees of the other criteria must be reconsidered too.
Treating the reference-point approach as a genuine second method. In this extension the reference-point step copies the ratio system's score and performs no independent calculation. Presenting the result as "confirmed by two methods" is wrong; in effect only one approach is at work.
The governing principle is this:
The contradiction degree is a criterion's share of independence or contradiction, drawn from measurable ground; an unjustified figure also makes the ranking produced by the ratio system unjustified.
Cases
The first case is DecisionMind's validation example. Smarandache's founding 2018 source defines the plithogenic operations but includes no example decision table; DecisionMind has therefore built a small, hand-traceable table using the same formulas. The second case is an illustrative fiction.
1. Illustrative example: Three alternatives, three criteria (DecisionMind validation example)
Three alternatives are assessed on three criteria. The first two criteria are "more is better", the third is "less is better". C1 is taken as the dominant criterion, with a contradiction degree of zero; the contradiction degrees of C2 and C3 relative to C1 are 0.33 and 0.67 respectively.
| Alternative | C1 (more is better) | C2 (more is better) | C3 (less is better) |
|---|---|---|---|
| A1 | (0.70; 0.20; 0.10) | (0.50; 0.30; 0.20) | (0.60; 0.30; 0.20) |
| A2 | (0.80; 0.10; 0.10) | (0.60; 0.20; 0.20) | (0.40; 0.20; 0.30) |
| A3 | (0.60; 0.20; 0.20) | (0.70; 0.20; 0.10) | (0.50; 0.30; 0.20) |
| Contradiction degree | 0.00 | 0.33 | 0.67 |
| Weight | 0.40 | 0.35 | 0.25 |
The method adjusts every cell by its own criterion's contradiction degree, draws a score from the adjusted triple, and shifts and normalises the score against its column magnitude. It then applies the weights and subtracts the "less is better" sum from the "more is better" sum.
| Alternative | MOORA score | Rank |
|---|---|---|
| A2 | 0.3089 | 1 |
| A3 | 0.2813 | 2 |
| A1 | 0.2739 | 3 |
The result reads as follows. A2 has the highest truth on C1 (0.80) and the lowest truth on C3, the cost criterion; these two criteria together carry a weight of 0.65 and carry A2 into the lead. The gap between A3 and A1 is small: A3 has the highest truth on C2, but this criterion's contradiction degree (0.33) is moderate.
The board's hesitation: had C2's contradiction degree been taken as 0.55 instead of 0.33, with everything else held constant, A1 would move ahead of A3 with 0.2780, just above A3's 0.2777, which sits just below that same 0.2780 mark; the difference is very small, but the ranking reverses. When the degree is raised to 0.90 this gap widens and A1 moves clearly ahead of A3 (A1 0.2844, A3 0.2728). A2 stays first throughout all these scenarios, because it holds the best position on both C1 and C3. This shows how much the contradiction-degree assumption determines the ranking outside of A2's position.
In the report: "With the given weights and contradiction degrees (C1=0, C2=0.33, C3=0.67), A2 has the highest net score (0.3089). The gap between A3 (0.2813) and A1 (0.2739) is small, and their ranking reverses once C2's contradiction degree is raised to 0.55."
Source: DecisionMind's P-MOORA manifest, validation example. The plithogenic operations (contradiction adjustment) rest on the formulas defined by Smarandache (2018); since the founding source gives no example decision table, the table has been constructed by DecisionMind faithfully to the formulas. The MOORA scores and sensitivity scenarios were independently recomputed by this card's author with the same algorithm, matched exactly against the kernel code.
2. Textiles: A manufacturer's choice of new fabric-finishing method
A textile manufacturer is to choose among three finishing methods for a new order. Three criteria are used: colour fastness, post-weaving strength and processing time (the last "less is better"). The production engineers take colour fastness as the dominant criterion. They judge strength to be partly in conflict with colour fastness, because some dyeing methods reduce strength, and they judge processing time to carry information more independent of colour fastness, setting the contradiction degrees accordingly. Each method is scored on each criterion with a truth-indeterminacy-falsity triple; the indeterminacy comes from the small number of tests run.
The method adjusts the three alternatives by their own contradiction degrees, scores and normalises them, applies the weights and computes the ratio-system score. Suppose the method with the highest colour fastness also has the longest processing time; it still comes first, because the weight on colour fastness exceeds that on processing time.
The engineers' hesitation: if processing time's contradiction degree has been kept low, that is, treated as information independent of colour fastness, this method's real delivery risk may not carry enough weight in the ranking. The manufacturer should not decide on the net score alone without applying delivery time as a separate screening criterion.
In the report: "With the high weight given to colour fastness, the method with the highest fastness value ranks first; because the contradiction degree of processing time has been kept low, a separate upper bound is recommended for delivery risk."
3. What Not to Do
Raising or lowering C2 and C3's contradiction degrees in the illustrative example arbitrarily, "to widen the gap": the degrees must rest on a justification about the criterion's independence and must not be chosen to pull the ranking in a desired direction. The second error is reducing the T-I-F triples to a single number first, for instance keeping only the T value, and then running crisp MOORA; this erases indeterminacy at the first step and destroys the plithogenic form's only contribution. The third error is presenting the reference-point step's result as a second, independent verification of the ratio system; in this extension that step merely copies the same score.
Sources
For the formulas behind each step, the intermediate tables and citation formats, see the DecisionMind method page: decisionmind.app/library/p-moora
Brauers, W. K. M., & Zavadskas, E. K. (2006). The MOORA method and its application to privatization in a transition economy. Control and Cybernetics, 35(2), 445–469. (no DOI)
Brauers, W. K. M., & Zavadskas, E. K. (2009). Robustness of the multi-objective MOORA method with a test for the facilities sector. Technological and Economic Development of Economy, 15(2), 352–375. DOI: 10.3846/1392-8619.2009.15.352-375
Smarandache, F. (2018). Plithogenic Set, an Extension of Crisp, Fuzzy, Intuitionistic Fuzzy, and Neutrosophic Sets – Revisited. Neutrosophic Sets and Systems, 21, 153–166. DOI: 10.5281/zenodo.1408740
Smarandache, F. (2017). Plithogeny, Plithogenic Set, Logic, Probability, and Statistics. Pons Publishing House, Brussels. (no DOI)
Abdel-Basset, M., & Mohamed, R. (2020). A novel plithogenic TOPSIS-CRITIC model for sustainable supply chain risk management. Journal of Cleaner Production, 247, 119586. DOI: 10.1016/j.jclepro.2019.119586